1. Field of the Invention
The present invention relates to a data processing apparatus, namely, a computer system. Particularly, it relates to a computer system in which storage resources are previously reserved to be allocated to job groups.
2. Description of the Prior Art
A computer system such as a main frame is used by many users. The computer system includes an external storage apparatus. When a user executes a job by opening a file, a part of the external storage apparatus is allocated to the file. The most common external storage apparatus is a magnetic disk system. In this specification, the external storage apparatus such as a magnetic disk apparatus is simply called a "storage". A magnetic disk system is composed of a plurality of magnetic disk units, and these units are generally called "volumes". In the following, this term "volume" is used to express the magnetic disk unit. Generally, when a file is opened, a user can directly indicate a number of the volume in which a storage region is allocated to the file. When the user performs the job under an application program, the volume number of the application program is previously decided, and the application program automatically indicates the volume number. Therefore, the user does not need to indicate the volume number. However, in this case, the application program also indicates the volume number.
When the computer system is individually used by independent users, there is no problem with the above allocation method of storage. However, in organizations such as companies, all business operations are divided into individual operations, for example, sales, production, accounting, and budgets are decided for each operation and all costs are calculated for each operation. Consequently, when a computer system commonly used for the above operations is implemented, the processing ability of the computer, such as arithmetic operation speed, and the total capacity of a storage apparatus is decided according to analysis of present jobs and predicted future jobs of all related operations, and storage volumes are reserved for each operation. Of course, there are storage volumes which are not reserved, and these un-reserved storage volumes are used in common. In the practical operations of a computer system, all costs of operating the computer system are calculated for each individual operation.
In the above, sales, production, and accounting are shown as examples of operations. However, the term "operation" is not limited to above examples. For example, a development project can be an "operation" if particular units of the storage are reserved for this development project for processing data relating to this development project. In this specification, a job group which has an exclusively reserved storage in the computer system is called an "operation".
FIG. 1 is a diagram illustrating operations of the storage volume allocation in the prior art. As shown in FIG. 1, in the computer system of the prior art, a manager 100 of the computer system or a manager of the storage system makes a storage reservation rule table 101 in which corresponding relationships between operations and storage volumes reserved for those operations are indicated, and a print out of the above table are given to each user. When a user 102 uses the storage for a particular operation, the user finds the volume numbers of the storage reserved for that operation according to the table 101 and makes a request to the job manager 104 of the computer system 103 to allocate the storage reserved by indicating the volume number. In response to this request, the job manager 104 of the computer system allocates the storage region in the indicated volume of the storage system.
In the table 101 shown in FIG. 1, volumes 10 to 15 are reserved for an operation A, volumes 16 to 22 are reserved for an operation B, volumes 30 to 39 are reserved for an operation C, and so forth. When the user 102 is going to perform a job included the operation A, the user makes a request for file allocation by indicating one of the volumes 10 to 15. This storage allocation request is performed by using a Job Control Language (JCL). If the user makes the request for the storage allocation by indicating, for example, the volume 16, either by mistake or intentionally, the job manager 104 allocates a storage region in the volume 16 to the job in which the user is going to perform the operation A.
As described in above, in the storage management apparatus of the prior art, the manager of the computer system makes the storage reservation rule table, and the user indicates the storage volumes according to this table. Namely, the management of the storage is carried out manually. Therefore, it is not assured that the storage reservation rules given in the table are always observed. As described in above, the storage reservation rules are decided according to practical analysis in order to realize the efficient utilization of the storage. Consequently, when the storage reservation rules are not observed, a problem occures in that the storage is not efficiently utilized. Further, when the volume reservation rules are not observed, a storage volume reserved for a particular operation stores data relating to other operations. Consequently, another problem occures in that fine management of the storage is difficult.
In the computer system, storage information, such as information relating to practical utilization of space and changes therein, is collected, and this information is analyzed to improve the efficiency of the storage. When the analysis is performed in the computer system of the prior art, the information is collected for each storage volume of the storage apparatus, and a person, for example, a manager of the computer system, checks the correspondence between the volumes and the operations according to the storage reservation rule table and classifies the volumes for each operation. Then, the states of the storage volumes reserved for each operation are analyzed. Namely, the collection and classification of the storage information is carried out manually. Therefore, when the analysis of the storage of each operation is performed, problems occure in that the analysis is very complicated because the classification of the storage information is required. Further, when the storage reservation rules are not observed, the classification of the storage information becomes more complicated because storage information corresponding to two or more kinds of operations are stored in one volume of the storage.
As described in above, in the computer system of the prior art, only analysis of the total storage is possible, and fine analysis of each storage is very difficult.
In the computer system, back-up procedures of the storage are performed in order to prepare for the occurrence of failures, and recovery procedures of the storage are performed when failures occur. In the computer system of the prior art, when the above back-up and recovery procedures are performed for storage volumes reserved for each operation, the recovery requires indication of the storage volumes reserved for each operation according to the storage reservation information. Namely, the above procedures for each operation cannot be performed only by indicating the name of the operation. Therefore, the back-up and recovery procedures become complicated.
In the computer system, the arrangement of used and unused space of the storage is occasionally performed. In the computer system of the prior art, when the storage space arrangement procedures are performed for storage volumes reserved for each operation, the space utilization states of the storage volumes reserved for each operation are first examined, and then someone personally makes the arrangement indication to all storage volumes reserved to that operation according to the space utilization states. Therefore, the arrangement of the storage space utilization becomes complicated. Further, the storage utilization methods of respective operations are usually different, therefore, the storage space arrangement is desirably different for each operations. However, when the storage reservation rules are not observed, the individual storage space arrangement corresponding to each operation cannot be efficiently performed because storage volumes reserved for a certain operation contain data of different operations.